Labels have been developed in the past of the type which are mounted on a surface with pressure sensitive adhesive, and which are designed to resist abrasion and exposure to weather. Such a label may include a protective, transparent laminating ply mounted over the label ply carrying printed information. Labels of this type may, for example, advantageously be employed as validation labels for use on automobile licenses, and in other applications where harsh environmental conditions are encountered. One example of such a label construction is shown in U.S. Pat. No. 2,783,172, issued Feb. 26, 1957, to Avery. The Avery patent discloses a laminated label structure in which each label consists of an intermediate layer of acetate or similar transparent material with a pressure sensitive adhesive on its lower surface, mounted on a backing sheet. The label structure of the Avery patent further includes a label layer having a pressure sensitive adhesive on its lower surface, mounted on the intermediate layer. In use, information is initially printed on the label layer of the Avery patent. The label layer is then removed and applied to a surface. Finally, the intermediate layer is removed from the backing sheet and applied over the label layer.
The labels disclosed in the Avery patent are provided on backing sheets carrying a plurality of such labels; they are not included on business forms. Further, if such a multiple ply label were to be mounted on a business form, the label surface would be raised significantly above the surface of the business form. It will be appreciated that this could result in a business form that would not be easily printed by some types of printers, such as for example laser printers.
The method by which the labels of the Avery patent are constructed has certain drawbacks, as well. Specifically, in the Avery patent, a removable backing sheet, a transparent acetate sheet and the label paper are fed in continuous sheet form into a label making press. Adhesives are applied to the undersides of the acetate sheet and label paper, and the three sheets are led under a pressure roller. The resulting laminated sheet is then fed to die cut rollers where the label sheet and the acetate sheet are cut. The cuts made in the label sheet are made against the backing of the acetate sheet, which may not be as hard as is desired for a clean cut. The matrix material between the labels thus formed is then stripped away. The labels in the Avery patent may then be printed, or printed at a later time. It will be appreciated that any scrap created during the press make ready operation will include the transparent acetate material as well as the label material, thus increasing the cost of such scrap.
Other desirable label innovations include tamper evident features wherein a laminate structure includes an opaque layer which upon de-lamination preferentially separates so that a warning word, such as "VOID" is displayed the label, on the surface from which it was removed, or on both surfaces. Commercial products which provide label manufacturers with the components needed to manufacture tamper evident labels have been available. Examples of such materials include: Scotch.TM. Protected Graphics Systems and Securmark.TM., both available from Minnesota Mining and Manufacturing Company, St. Paul, Minn., and Tampermark.TM., available from FLEXcon Company, Inc., Spencer, Mass.
There is a need for a business form that includes a label that provides protection from environmental conditions, that is easily manufactured, that provides tamper evident features, and that is simple and effective in use.